Ski boots are the most important part of any skier’s setup. A properly fitted ski boot helps transfer power from your body to your skis and bindings, giving you better control, comfort, and confidence on snow. Ski boots that are too big can feel sloppy and reduce control, while boots that are too small or the wrong shape can cause pain, numbness, or pressure points.
The best ski boots for you depend on your foot shape, mondo size, boot last, flex, ability level, skiing style, and whether the boot is compatible with your bindings. The Pro Ski and Ride is a specialty boot fitting shop, and we strongly recommend working with a professional boot fitter whenever possible. If you are shopping online, this guide can help you better understand ski boot sizing, fit, flex, and features before choosing your next pair!
Step 1: Choose the Right Ski Boot Size
Ski boots are sized in mondopoint, often called mondo sizing, which is based on the length of the foot in centimeters. For example, a skier with a foot that measures approximately 26.5 centimeters would generally start by trying a 26.5 mondo ski boot. Mondo sizing is more accurate than regular shoe sizing, but it is still only a starting point. Foot shape, instep height, width, skier ability, and fit preference all affect which size will work best.
Below is a chart converting mondo to US men's and women's sizing. Please keep in mind, many people wear their shoes a half size or size too big. It is common to size down from street shoes to ski boots.
| Mondopoint |
US Men's / Unisex |
US Women's |
| 21.5 |
3.5 |
4.5 |
| 22.5 |
4.5 |
5.5 |
| 23.5 |
5.5 |
6.5 |
| 24.5 |
6.5 |
7.5 |
| 25.5 |
7.5 |
8.5 |
| 26.5 |
8.5 |
9.5 |
| 27.5 |
9.5 |
10.5 |
| 28.5 |
10.5 |
11.5 |
| 29.5 |
11.5 |
- |
| 30.5 |
12.5 |
- |
| 31.5 |
13.5 |
- |
Step 2: Choose the Right Ski Boot Last and Volume
Ski boot last refers to the width and overall volume of the boot, especially through the forefoot, instep, and ankle area. Boots are commonly offered in low volume, mid volume, and high volume fits, with race boots and extra-low-volume boots providing an even more precise fit. Measurements vary by brand, but in a men’s 26.5 mondo size, a low-volume boot is often around 98 mm wide, a mid-volume boot around 100 mm, and a high-volume boot around 102 mm. Although those numbers seem close, even 2 mm can make a major difference in ski boot fit.
Step 3: Pick the Right Ski Boot Flex
Ski boots come in a variety of stiffness levels referred to as flex. Flex is not a standard measurement, but gives you an idea of how hard it will be to bend your knees forward when skiing. The stiffer the flex, the more responsive the boot. Buying a boot that is too soft will feel lacking when it comes to controlling the skis. But stiffer is not always better. Buying a boot too stiff will make it difficult to bend your knees getting your energy to the tips of the skis.
Stiffness is counted on a scale from 50 - 150. Generally, the higher the number the stiffer the boot. The higher the number also indicates where the boot is in a product line and may come with additional features and/or better materials in addition to being stiffer than boots with a lower number.
Soft flexing ski boots are generally below 100 for men or 80 for women. These are suited towards beginner or intermediate skiers.
Medium flexing boots are 100 - 110 for men and 80 - 90 for women. These boots are best suited for intermediate to advanced skiers. Weight and strength play a large role in determining flex so lighter weight advanced skiers or heavier beginners could find themselves in this range as well.
Stiff boots are above 110 for men and above 90 for women. These boots are generally best for advanced to expert skiers who ski aggressively on a consistent basis.
Step 4: Consider Ski Boot Customization and Boot Fitting
Most ski boots can be customized to your feet by a professional boot fitter. A proper boot fitting can increase comfort and performance in nearly any boot. Here are some common adjustments that can be customized:
Heat Molding - Most quality boots sold have liners that can be heat molded for varying degrees of customization. Specially calibrated hot air is blown into the liners making them pliable. When a skiers feet are put in the heated liners the material is compressed in areas that were previously tight.
Some manufacturers also make shells that can be put into a boot oven to create a custom shaped shell!
Canting - Many boots have the ability to adjust the cuff to better match the leg angle this could be on one side of the boot or on both sides of the boot providing even more adjustment.
Forward Lean Adjustment - Some boots have the ability to adjust the lean of the cuff over the toes to make it more aggressive or relaxed.
Flex Tuning - Many boots have the ability to adjust the flex of the boots such as a "ski soft / ski hard switch" or bolts that can be removed from the back. These changes can often be made without the assistance of a boot fitter.
Step 5: Compare Ski Boot Features
Tech Inserts - Tech inserts allow for boots to be used with alpine touring pin bindings. They are not needed for normal alpine skiing.
Ski/Hike Switch - A ski/hike switch allows for increased range of motion while in hike mode. When in ski mode the cuff is locked in a forward, skiing position.
GripWalk Soles - GripWalk soles allow for easier walking with a slightly rockered toe and increased grip. Make sure your bindings are compatible with GripWalk soles if you are considering purchasing boots with these soles installed.
Step 6: Add Support with Custom Footbeds
Nearly all ski boots come with a flat stock foot bed with no arch. These flat insole do no harm but certainly do not help. Consider purchasing an aftermarket footbed that can be customized to your feet. Options range from pre-shaped footbeds that can be used as is or custom molded to completely custom orthotics.
At The Pro we recommend
BootDoc Comfort Footbeds. These are suitable for nearly all skiers coming in three arch types. They are pre cut to fit in boots and can be used out of the box. They can also be custom molded to hone in the arch support you need.
Frequently Asked Ski Boot Buying Questions
How should ski boots fit?
Ski boots should feel snug and secure without causing sharp pain, numbness, or major pressure points. Your toes may lightly touch the front of the boot when standing upright, but they should pull back slightly when you flex forward into a skiing stance.
Should I size down from my regular shoes for ski boots?
Many skiers wear street shoes that are larger than their measured foot size, so it is common to end up in a ski boot that sounds smaller than your normal shoe size. Mondo size, foot shape, and shell fit are more important than matching your everyday shoe size.
What ski boot flex should I choose?
Ski boot flex depends on skier ability, weight, strength, and skiing style. Softer boots are usually better for beginners and lighter skiers, while stiffer boots are better for stronger, more aggressive, advanced skiers.
What does ski boot last mean?
Ski boot last refers to the width and overall fit volume of the boot. A low-volume boot fits narrower feet, a mid-volume boot fits average feet, and a high-volume boot fits wider or higher-volume feet.
Are GripWalk ski boots compatible with all bindings?
No. GripWalk boots must be used with GripWalk-compatible or Multi-Norm Compatible bindings. Always check binding compatibility before skiing in new boots.
